CVE-2020-11633

9.8 criticalEPSS 1.9%

Critical (9.8) in zscaler client connector. EPSS 1.9% chance of exploitation in the next 30 days.

The Zscaler Client Connector for Windows prior to 2.1.2.74 had a stack based buffer overflow when connecting to misconfigured TLS servers. An adversary would potentially have been able to execute arbitrary code with system privileges.

Severity

CVSS 3.1

9.8 critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 1.9% chance of exploitation in the next 30 days; higher than 79% of CVEs (scores of 2026-10-31)
CWE: CWE-787
Published: 2021-07-15
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

zscaler:client_connector

References

https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2020?applicable_category=Windows&applicable_version=2.1.2.81
https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2020?applicable_category=Windows&applicable_version=2.1.2.81

Check your stack JSON